An introductory word: Thanks to Dominic Cummings, I have a lot of new readers, many from the United Kingdom, so I want to welcome all of you, and I hope at least some of you will stay when I turn to non-Covid questions. I am American so these posts focus on the United States, but I keep an eye elsewhere too, and mostly we’re all in this one together and the same conclusions apply. If you have good news sources and follows to keep a better eye on the UK or Europe for Covid purposes, or data sources anywhere I may not have noticed, I invite you to share them in the comments.
The constant refrain from all sources is ‘we will know more soon.’ Soon is continuously arriving. The new information we are learning hasn’t completely ruled out many possibilities, but it is broadly consistent with Omicron spreading fast and having a high degree of immune erosion/escape in terms of infection but not protection against severe disease.
Thus, to headline the core takeaways at the top, here’s broadly where I’m at as of now (probability estimates at the end, as before). I’d be surprised if any of these were wrong.